1. Field of the Invention
The invention relates to a hinged tooth for a cutting wheel comprising a pivot bearing for pivotally supporting on a pivot pin located on a cutting wheel hub, a cutting tooth support extending from the pivot bearing and a steering arm extending from the pivot bearing substantially in a direction opposite to that of the cutting tooth support.
2. Related Art
Hinged teeth of such kind are known from EP 0 291 027 B1 which also originates from the applicant. In trench cutters having cutting wheels arranged laterally on a bearing shield there exists the problem that the soil located immediately below the bearing shield cannot be worked off directly by the cutting wheels. It is therefore suggested in EP 0 291 027 B1 that the cutting teeth adjoining the bearing shield are hinged on the cutting wheels. Through a kind of cam steering the hinged teeth can be swung out in an area below the cutting shield in order to work off the soil lying underneath, while a further turning of the cutting wheel causes the hinged teeth to be swung in again so that the bearing shield is not damaged by the cutting teeth.
For functional reasons and on account of their required inclination the hinged teeth are exposed to considerable forces and stress, in particular if a more compact soil or a rocky underground needs to be worked upon. Hence, the known hinged teeth are exposed to excessive wear and can also suffer from premature damage for which reason an early exchange is required. However, not only does an exchange of the hinged teeth lead to relatively long and therefore costly downtimes of the high-investment trench cutter but in addition the hinged teeth are relatively expensive on account of the pivot support required for them and the demanded wear resistance.